WO2016005179A1

WO2016005179A1 - Apparatus for generating light having a plurality of wavelengths, method for manufacturing an apparatus, use of a positioning module, method for combining light beams, and apparatus for generating light having a plurality of wavelengths

Info

Publication number: WO2016005179A1
Application number: PCT/EP2015/064025
Authority: WO
Inventors: Hansruedi Moser; Marcel Wäspi; Patrick Spring
Original assignee: Fisba Optik Ag
Priority date: 2014-07-08
Filing date: 2015-06-23
Publication date: 2016-01-14
Also published as: EP3167329B1; US20170153009A1; US10598951B2; EP3167329A1; EP2966490A1; JP2017523609A

Abstract

An apparatus for generating light having a plurality of wavelengths comprises a housing (1) and light sources (2) inside the housing (1). The light sources (2) are especially in the form of laser diodes. Preferably, three light sources having different wavelengths are formed. The apparatus further comprises collimating lenses (3) for collimating a light beam emitted by the light sources (2), and beam guiding elements for bundling the light beams. The collimating lenses (3) are disposed in a positioning module (4) that allows the collimating lenses (3) to be placed in different positions during the apparatus manufacturing process.

Description

A device for generating multi-wavelength light, method for manufacturing a device, use of a positioning module, method for combining light beams and device for generating light with multiple wavelengths

The invention relates to a device for generating light having a plurality of wavelengths, a method for producing a device, the use of a positioning module, a method for combining light beams and a device for generating light with multiple wavelengths according to the preamble of the independent claims.

Projection modules are already known which can project light with different colors in a miniaturized design.

Such a projection apparatus is known for example from the WO 2013/178280, in which there is disclosed that three light sources ^¬ emit light, the light is combined in a beam combiner into a beam and is then projected through a MEMS mirror onto a screen. Furthermore, a Virtual modifying means is formed, which modifies the single ^¬ colors together into a round beam diameter. Such a device is very complex and with their many construction ^¬ share very difficult to miniaturize and at the same time produce exactly. Furthermore, the luminous efficacy is poor.

From WO 2014/023322 a projection device is furthermore known in which laser diodes are arranged parallel next to each other, wherein the laser diodes are glued into recordings. Inaccuracies in the alignment of the laser diodes are compensated in such a way that the laser diodes are first fixed, and then mirrors are used on the one hand to combine the light beams and to correct the alignment errors of the laser diodes. the. This method is expensive to carry out and inaccurate in the orientation of the diodes.

It is therefore an object of the present invention to avoid the disadvantages of the prior art and in particular an on ^¬ direction and to provide a method, with the best possible superimposition of the individual colors, a high luminous efficiency and a simplified production is possible. The object is solved by the characterizing part of the independent claims.

In particular, the object is achieved by a device for the generation ^¬ supply of light of multiple wavelengths, which comprises a housing. In the housing light sources are arranged, in particular laser diodes. Preferably, there are three light sources each having different wavelengths. Furthermore, the housing comprises collimating lenses for collimating a light beam emerging from these light sources. In addition, the apparatus includes beam guiding elements for converging the light beams. The collimating lenses are arranged in a positioning module, which light-positioning of the Kollimie ^¬ approximately lenses in different positions within the positioning module in the manufacturing process of the device enables.

Such a device is easy and automated forth ^¬ adjustable and leads to a very precise superposition of the individual light beams.

In the device, exactly three light sources with the colors red, green and blue are preferred. Furthermore, it is possible to add a fourth light source, in particular a second green light Light source to optimize the light intensity in this particular color.

Between the light source and the collimating lens, no diaphragm is preferably arranged in order to be able to use the full light output of the light source.

An inventive positioning module is designed so that it allows easy positioning of the collimating lens, while the light source is already mounted in the housing. The

Positioning module is preferably a part of the device and remains even after production in the housing. The Positionin ^¬ insurance module preferably has a maximum dimension of 3x3x3 mm.

The positioning module can be a cube or a six-sided prism. Also possible would be an eight- or more-sided prism. Each lateral surfaces of the prism in this case act as support surfaces for the prism, so that, for example in egg ^¬ nem sixteenth side prism six support surfaces are formed.

A positioning module according to the invention has a front side and a rear side, wherein the front side is oriented toward the light source and the rear side away from the light source. Front and back are connected by side surfaces on which the positioning module can be placed. Between the front and back ^¬ side a collimating lens is arranged so that the light from the light source through the collimating lens is durchstrahlbar. The collimating lenses are attached ^¬ into the positioning module and positioned with the positioning module in the light beam from the light sources. Such a positioning module enables a simple Po ^¬ sitionieren of collimating lenses, at the same time sufficient space for accurately positioning and fixing the position is available. When positioning the positioning module, it is simultaneously possible to compensate for any alignment errors of the light sources at least partially.

The collimating lens in the positioning module can be arranged eccentrically, in particular with respect to the side surfaces of the positioning module.

By an eccentric arrangement of the lens in the positioning ^¬ module, the position of the lens by rotating the positioning module and arranging on another side surface one

Correct a possible alignment error of the light source.

The positioning module can be made of metal, in particular aluminum or steel, or else already completely made of glass.

The positioning module is preferably stuck in the device ^¬ , wherein in the metering of the adhesive shrinkage during curing or drying is taken into account. The

Beam guide elements may comprise dichroic mirrors, preferably a dichroic mirror per light source. With dichroic mirrors, the individual light rays can be guided to the correct position, align and at the same time merge into one ray. The beam guiding elements may comprise a prismatic telescope.

With a prism telescope, the beam diameter of the light beam can be optimized. Preferably, a prism telescope is used for the already combined light beam after the dichroic mirrors. However, it is also conceivable per light source to use a prism telescope in front of the dichroic mirrors. However, this is due to the required space disadvantageous for a miniaturized version. The prism telescope opti mized ^¬ the ratio of the two axes of the beam cross-section in the direction of 1, preferably in a range of 0.5 to 0.8.

The prism telescope can consist of individual prisms, which can be individually positioned for optimum alignment of the light beams.

This results in a precisely superimposed, the circular cross-section ^¬ form approximated as possible beam.

One of the light sources may be after the collimating lens in

Beam propagation direction, a retardation plate, preferably a lambda half λ / 2 (lambda half) plate include.

Can thus be, in particular in two same-colored light sources ^¬, change the polarization of the emitted light, so-that two beams of the same wavelength above the other can be placed. With the dichroic mirrors then the further wavelength are also combined in the beam. The housing preferably has a maximum extension of 5x15x25 mm (HxBxL). The housing is preferably made of aluminum, steel or copper, which is suitable for soldering. To achieve the object further leads to a method for producing a device, in particular as previously ^{¬ written} .

The method comprises the following steps:

Fix, preferably press, of at least three sources of light ^¬ in a housing; the light sources are in particular laser diodes;

Providing a positioning module;

- Positioning of collimating lenses in a light beam emerging from the respective light sources, using the positioning module;

Connecting positioning module and housing, in particular as a permanent connection;

- Positioning of beam guiding elements in a light beam after the Kollimierungslinsen for merging the individual light beams into a common light beam.

Such a method can be carried out automatically and allows an accurate alignment of the individual light beams and an optimized light output.

The positioning module makes it possible to position the collimating lens in three dimensions, namely position along the direction of propagation of the light from the light source (Z).

Direction), perpendicular to the propagation direction (X direction) and perpendicular to the propagation direction and to the X direction (Y direction). The Y direction is also referred to as altitude. The Po Positioning in the Y direction is possible to a very limited extent by means of an eccentrically arranged collimating lens, without the beam becoming too asymmetrical.

The respective positioning modules can be glued. Preferably, the positioning modules are first positioned and then glued.

A eingeklebtes positioning module can be flexibly posi ^¬ tioning and fix it. Furthermore, a precise knowledge of the adhesive also allows the consideration of the required quantity for the exact height positioning of the collimating lens.

When gluing the positioning modules, the amount of adhesive and / or the Klebspaltgröße be chosen so that a shrinkage occurring during curing of the adhesive is taken into account.

Thus, the position of the positioning module and there ^¬ with the collimating lens can be determined and adjusted very accurately.

The adhesive can be epoxy.

The beam guiding elements can dichroic mirrors umfas ^¬ sen, the positioning elements are positioned so that any differences in height between a ^¬ individual laser beams are balanced. For this purpose, the positioning elements are aligned so that all light rays are arranged at the same height on the mirrors. By positioning the mirrors and positioning elements, it is possible to compensate for inaccuracies in all three directions (X, Y, Z direction). In particular, a compensation of the height differences is achieved by positioning the positioning elements realized. Thus, the achievement of a very precisely superimposed common beam is possible.

To achieve the object further leads to the use of a positioning module for positioning lenses, in particular collimating lenses.

The independent positioning of the positioning module with the collimating lenses leads to an easy way to correct alignment errors of light sources and to achieve an exact and stable collimation.

To achieve the object further leads to a method for combining light beams, wherein the light beams from at least two light sources, preferably laser diodes, are each collimated with a collimating lens. The Kollimierungslinsen are each arranged in a positioning module. The collimated beams are combined into a combined beam by beam guiding elements.

Such a method is easy to perform and results in a combined beam with high light intensity and the greatest possible coverage of the individual colors from the light sources.

To achieve the object further leads to an apparatus for generating light having a plurality of wavelengths, comprising a housing and arranged in the housing light sources, in particular laser diodes. Preferably, three light sources, each with different wavelengths, are formed. The apparatus further comprises collimating lenses, preferably collimating lenses in a positioning module, for collimating a light beam emerging from the light sources and beam guiding elements to merge the light beams. The light sources are fixed in the housing by a press fit.

Such a device leads to an optimum heat transfer of the heat, which is generated by the light sources, into the surrounding housing. The light sources are pressed into the housing and are no longer adjusted. Such introduced Lichtquel ^¬ len are very quick to install and there are no expensive adhesives, filling and alignment processes perform.

Such a device preferably has a positioning ^module as described above.

Include the beam guiding elements preferably a Prismentele- microscope as previously described and dichroic mirror, a dichroic mirror vorzugt be ^¬ per light source.

The device may include a retardation plate that alters the polarization of light from a light source to the collimating lens.

Thus, several light sources with a color through the dichroic mirror can be combined. The invention will be explained in more detail with reference to figures in exemplary embodiments. Hereby shows:

1 shows a perspective view of a housing with Po ^¬ sitionierungsmodulen,

FIG. 2: a schematic top view of a device according to the invention, FIG. 3: a cross section through a positioning module;

FIG. 4 shows a schematic plan view of a device according to the invention according to a further embodiment,

FIG. 5 shows a schematic top view of a device according to the invention for fiber coupling;

FIG. 6 shows a perspective, three-dimensional view of the device according to the invention;

Figure 7: A cross section through a positioning module. Figure 1 shows an inventive device with a Ge ^¬ housing 1. In the housing 1 four laser diodes are pressed (not visible). In front of the laser diodes four positioning modules 4 are arranged. The positioning modules 4 each have a collimating lens 3. The positioning modules 4 are used to align the light beams from the laser diodes. For this purpose, the openings in which the Kollimierungslinsen 3 are arranged eccentrically in the positioning module 4 angeord ^¬ net. Furthermore, the distance between the laser diode and positioning ^¬ nierungsmodul when positioning the positioning module 4 can be adjusted. The positioning modules 4 are glued to the bottom 9 of the housing 1. The amount of the adhesive is so dimensio ^¬ ned, that a correction of the height of the Positionierungsmo ^¬ duls 4 is set to the housing 1, wherein a shrinkage of the adhesive is taken into account. In the finished state, the housing 1 also has a lid (not shown).

FIG. 2 shows a plan view of an embodiment of the device according to the invention. The four light sources 2 emit a light beam to the dichroic mirror 5. The dichroic mirror 5 have been fixed after pressing the light sources 2 in the housing 1 on the housing 1. Thus, the dichroic mirrors 5 do not have the same distance from the respective light sources 2. In this embodiment, by way of example, two red light sources 2c, 2d are formed. One of the red light sources 2c is therefore changed in polarization by a retardation plate 7. Thus, the dichroic Spie ^¬ gel can be 5c pass through the red light from the light source 2d, and at the same time reflect the red light from the source 2c. The light from all the light sources 2 is further formed by the prism telescope 6 into a round beam. The Prismente ^¬ leskop 6 consists of a first prism 6a and a second prism 6b, which can be adjusted independently. For clarity, the lenses are shown in front of the light sources 2 without positioning module 4 (see Figure 3). However, the collimation in the embodiment is always performed with positioning modules 4. Figure 3 shows a section through a positioning module 4 with a collimating lens 3. The collimating lens 3 is used for Kollimie ^¬ ren of the light beam from the light sources 2 (see figure 1 and 2). The positioning module 4 enables a simp ^¬ che positioning of the collimating lens 3. Further, the collimating lens 3 eccentrically in the positioning module 4 angeord ^¬ net, so that, in this case a cubic Positionin ^¬ approximately module 4, four different positions of the lens are mög ^¬ Lich , FIG. 4 shows a plan view of an alternative embodiment of the device ^{according to} the invention. The embodiment of FIG. 4 corresponds to the embodiment of FIG. 2 without the use of a retardation plate 7. The light sources 2 emit light. In this embodiment, all different wavelengths, since a dichroic mirror 5 can not be formed by ^¬ casual and reflective for the same color simultaneously. All beam guiding elements are glued to the housing 1.

FIG. 5 shows an embodiment of a device according to the invention analogous to FIG. 2, wherein the emerging light beams from the device are coupled into an optical fiber 8. Such a device can be used in particular for medical purposes. In addition to the details shown in Figure 2, the device comprises a housing with a focusing lens 11, which focuses the exiting light beam in the optical fiber.

FIG. 6 shows a schematic three-dimensional view of a device according to the invention. The housing 1 comprises four

Light sources (not visible). In front of the respective light sources positioning modules 4 are arranged, in each of which a collimating lens 3 is arranged. With the help of Positionin ^¬ approximately module 4, the respective collimating lens 3 so that any errors in the alignment of the light source is already at least partially equalized by the collimating lens ^¬ positio ned ^¬. After exiting the positioning module 4, the individual light rays through the dichroic

Mirror 5 deflected and then brought by a prism telescope 6 in a round shape as possible. The prism telescope 6 consists of a first prism 6a and a second prism 6b which are individually positionable. Thus, a better roundness of the light beam can be achieved.

FIG. 7 shows a positioning module 4 according to the invention with four side surfaces 10. Onierungsmodul 4 on the bottom 9 of a housing 1 (see Figure 1) are set. The collimating lens 3 is positioned eccentrically in the positioning module 4. The distances h1, h2, h3 and h4 thus differ from one another and are matched to the tolerances of the emitter positions in the different laser diodes.

Claims

claims

Apparatus for generating light having a plurality of wavelengths comprising a housing (1), in the housing (1) arranged light sources (2), in particular laser diodes, preferably 3 light sources each having different wavelengths Kollimierungslinsen (3) for collimating a light beam from the light sources (2) emerges and beam steering ^¬ elements to the light beams merge, characterized in that the collimating lenses (3) are arranged in a Po ^¬ sitionierungsmodul (4) having a Posi ^¬ tioning of collimating lenses (3) in different positions in the manufacturing process of the device allows.

Apparatus according to claim 1, characterized in that the positioning module (4) is a cube or a six-sided prism.

Device according to claim 2, characterized in that the collimating lens (3) in the positioning module (4) is arranged exzent ^¬ driven.

Device according to one of the preceding claims, characterized in that the beam guiding elements comprise dichroic mirrors (5), preferably a dichroic mirror per light source.

5. Device according to one of the preceding claims, characterized in that the steel guide elements comprise a prism ^¬ telescope (6). Apparatus according to claim 5, characterized in that the prism telescope (6) consists of individual prisms which are individually positionable for optimal alignment of the light beams.

Device according to one of the preceding claims, characterized in that a light source (2) after the collimating lens in the beam propagation direction comprises a retardation plate (7), preferably a λ / 2 plate.

Process for producing a device, in particular according to claim 1, comprising the following steps:

- Fix, preferably press in, at least 3

Light sources (2), in particular laser diodes, in a housing (1);

- Providing a positioning module (4);

- Positioning Kollimierungslinsen (3) in one

Light beam emerging from the respective light sources (2) by means of a positioning module (3);

- Connecting positioning module and housing, in particular ^¬ special as a permanent connection;

- Positioning of beam guiding elements in one

Light beam after the Kollimierungslinsen (3) for merging the individual light beams to a common light beam.

A method according to claim 8, characterized in that the respective positioning modules (3) are glued.

A method according to claim 9, characterized in that when gluing the position modules (3) the amount of an adhesive and / or the contact pressure on the adhesive so be chosen that a shrinking on hardening of the adhesive ^¬ shrinkage is taken into account.

11. The method according to any one of claims 8 to 10, characterized, comprise that the beam guiding elements dichroic mirror (5), wherein the positioning modules (3) are positioned so that any existing Höhenun ^¬ differences of the beams on the mirrors (5) between be compensated for the individual light rays.

12. Use of a positioning module (4) for Positionin ^¬ tion of lenses, particularly collimating lenses (3).

13. A method for combining light beams, characterized in that light beams from at least two Lichtquel ^¬ len (2), preferably laser diodes, each collimated with a collimating lens (3), wherein the Kollimierlinsen (3) in a respective positioning module (4) are arranged, and together ^¬ menführen of the collimated beams into a combined beam by beam guide elements.

14. An apparatus for generating light having a plurality of wavelengths comprising a housing (1), in the housing (1) arranged light sources (2), in particular laser diodes, preferably three light sources (2) each having different wavelengths Kollimierungslinsen (3), preferably in one Positioning module (3), for collimating a light beam emerging from the light sources and beam guiding elements to merge the light beams, characterized in that the light sources (2) in the housing by a

Press fit are fixed. Apparatus according to claim 14, characterized in that the device comprises a retardation plate (7) which changes the polarization of light from a light source to the collimating lens (3).